19 February 2014

The International Council on Clean Transportation (ICCT) has published a report summarizing the results of its 2013 collaboration with the North American Council for Freight Efficiency (NACFE) on a survey-based study aimed understanding how the market for fuel-efficiency technologies for truck trailers has evolved and identifying opportunities for capturing additional efficiencies.

Data for the study, “Costs and adoption rates of fuel-saving technologies for trailers in the North American on-road freight sector,” were collected using telephone interviews of a number of stake-holders throughout the on-road trucking industry, including manufacturers of trailers, aerodynamic technologies, and tires, as well as large and medium for-hire and private trucking fleets that operate roughly between 250 and 10,000 tractors and 500 and 30,000 trailers. In all, the study team conducted telephone interviews with 22 companies.

Primary findings from the study include:

Costs of trailer side skirts have decreased substantially over the past 3 to 5 years. Current costs for trailer aerodynamic technologies—particularly side skirts—have decreased significantly in recent years, due to far more market entrants driving
cost competition and much higher deployment volumes reducing cost per unit. The authors estimated that prices for side skirts have dropped roughly 70% compared to estimates that were compiled as part of the 2010 National Academy of Sciences study that investigated fuel efficiency technologies for commercial vehicles.

A consensus position from the interviewees was that California’s tractor-trailer GHG regulation has been the primary driver for the rapid uptake and cost reductions of technologies but that an increasing number of fleets are adopting these aerodynamic devices because of attractive economics as well as improvements in the reliability and durability of products.

Among aerodynamic technologies, side skirts have had the largest rate of adoption, while the uptake of underbody, rear-end, and gap reduction devices has been more limited. The study team estimated that approximately 40% of new box trailers are sold with side skirts. Uptake of both underbody and rear-end devices is estimated to be roughly 3% of new box trailer sales, while sales of gap reducers have been fairly negligible and primarily limited to fleets that pair their trailers with day cabs.

There is widespread utilization of conventional-size low rolling resistance tires, but adoption of wide base tires has been slower. The data suggest that approximately half of all tractor and trailer tires sold are low rolling resistance (i.e., SmartWay-verified) tires. Responses from tire manufacturers and trucking fleets put the current uptake of wide base single tires at around 10% of new trailer sales. Maintenance issues—and perceptions of maintenance issues—for these tires and wheels continue as one of the primary barriers to adoption.

Roughly one-quarter of all trailers on the road in the US have at least one aerodynamic technology (e.g., side skirts, underbody device, or boat tail).

There are further improvements and efficiency gains that stand to be achieved in trailer aerodynamics and tire technologies.